The Blues have a good problem in that they have five top six wingers and only four spots. I'd agree with you that Kyrou probably shouldn't be playing his off wing, and that if anyone is it should be Perron. But while I really like Kyrou, I don't love the idea of throwing him onto the top line just yet. If I was configuring the lineup this is how I would have done it:

Perron - O'Reilly - Buchnevich
Saad - Schenn - Tarasenko
Neal - Thomas - Kyrou

Buchnevich is a top line forward who performed extremely well with Kreider and Zibanejad, he should be playing a prominent role here on our top line. That Perron-O'Reilly-Buchnevich line could be extremely dangerous.

For me Kyrou's path to the top 6 is really through Tarasenko. Kyrou faded pretty hard last season, so there's no reason to force him into the top six, where for Tarasenko there absolutely is (he needs to get his trade value up). By stashing Thomas and Kyrou on the third line, they have the opportunity to use weaker-than-top-line competition to build chemistry with each other, which will be good to develop now because they'll hopefully be playing together for a long time yet. It also forces Tarasenko into the top six to have plenty of ice time to get re-acclimated and get his value up. Kyrou should also get plenty of power play time on the top unit. When Tarasenko gets moved, if there's an injury, or if he just flat out outperforms someone else, that's Kyrou's opportunity into the top six. Although, if Neal keeps it up, I might run those middle two lines about evenly. Schenn was way too overexposed last year, so moderately reduced ice time will probably help his game as much as increased ice time will help Thomas.

I do also like Kyrou with Thomas. And I agree that Buch and Vladi probably should be given some extra ice time. Buch because he can flat out play and for reasons you already suggested with Vladi. Neal is fricken slow as **** though lol.